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Occurrence Details


Occurrence Number
105F 135
Occurrence Name
Ukon Showing 5
Occurrence Type
Hard-rock
Status
Showing


General Information

Primary Commodities: uranium
Aliases: Guano
Deposit Type(s): Unknown
Location(s): 61.505170 N, -132.445340 W
NTS Mapsheet(s): 105F09
Location Comments: Georeferenced from Map 14 in AR 095343 (p. 625).
Hand Samples Available at YGS: No

Capsule

Work History

Staked as Guano, etc. cl (YA00242) in Jul-Sep/76 by Ukon Joint Venture (Chevron and Kerr Addision), which explored with mapping, geochem and radiometric surveys in 1976. In 1977, hand trenching and rock sampling was carried out. A ground radiometric grid survey and rock and chip sampling was undertaken over the occurrence in 1979. Restaked as PS cl (YB00978) in Aug/87 by Mountain Province Mining Inc, which took one rock sample from the claim block in an undisclosed location. In 2010, soil sampling took place just east of the occurrence and a helicopter radiometric survey was flown over the entire property.
 
Regional Geology
 
The occurrence is located on the Cassiar Platform, a curvilinear shelf that formed in the early Paleozoic, roughly parallel to the western margin of the North American craton but separated from it by the Selwyn Basin. Shallow marine miogeoclinal sediments were emplaced on the platform until Late Devonian time. Block faulting and local uplift during the Late Devonian and Mississippian resulted in deposition of carbonaceous shale and chert pebble conglomerate in the Selwyn Basin and across the platform. Local explosive volcanism produced volcaniclastic material and flows of the Pelly Mountains volcanic belt. The belt comprises localized submarine volcanic centres generated in an extensional environment that are separated by basins in-filled with sediments and volcaniclastic rocks. Several cogenetic syenite and trachyte domes and small stocks are the remains of vent areas. Subsequent deformation is a result of Mesozoic thrust faulting related to the Cordilleran orogeny, emplacement of Cretaceous intrusions and Tertiary strike-slip movement along the major northwest-trending Tintina Fault, 30 km to the northeast.
  
Property Geology
 
The occurrence is hosted in the Devonian syenitic True Blue pluton. It was first identified as showing #5 in AR 090269. Float rock that assayed 0.481% U3O8 was found at the site in 1976. Radioactivity is associated with fine-grained grey-green dykes cutting syenite. The best mineralized float appears to be from 3-4 cm wide quartz-rich veins in the syenite. Two hand trenches (80 cm deep) in 1977 did not reach bedrock. Two samples of the most radioactive quartz-rich float assayed 0.352% U3O8 and 0.481% U3O8. The radioactive float is sparsely distributed through the area. Uranium assays are less than the level of radioactivity would suggest, which could indicate that the major radioactive component is thorium, rather than uranium.
 
Grab samples and a profile of chip samples collected in 2010 as part of a rare earth exploration program did not return any samples with anomalous REE or Zr concentrations.

Location Map

Last Updated: Mar 30, 2020

Work History

Year Work Type Comment
1987 Geochemistry: Rock
1979 Geochemistry: Rock
1979 Ground Geophysics: Radiometric Survey
1977 Geochemistry: Rock
1977 Trenching: Hand
1976 Airborne Geophysics: Gamma-Ray Spectrometry
1976 Geochemistry: Rock
1976 Geology: Detailed Bedrock Mapping
1976 Ground Geophysics: Radiometric Survey

Regional Geology - Terrane

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Regional Geology - Bedrock

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Related References

Number Title Page(s) Document Type
MIR1976 Mineral Industry Report 1976 Annual Report
YEG1979_80-pg55 Rare earth elements in the Guano-Guayes skarn property Pelly Mountains, Yukon Territory Annual Report Paper
1979Chronic Geology of the Guano-Guayes rare earth element bearing skarn property, Pelly Mountains, Yukon Territory MSc Thesis
Citations

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